Pastor Maldonado says Williams will have its "work cut out" on Saturday morning following a heavily disrupted Friday practice ahead of the Japanese Grand Prix.

Maldonado was forced to stop in FP1 after an oil pressure spike caused by an off-track excursion worried the team. Having only completed eight laps, a more productive afternoon session was required, but Maldonado pulled off track not long after team-mate Rubens Barrichello had crashed, and he said that he needed all of the track time he could get.

"An engine problem caused me to stop early in P2," Maldonado said. "It's my first time at Suzuka so I really need some more laps. We'll have our work cut out in tomorrow's final session."

Barrichello's crash happened on the entry to Degner One, and he said that the car had not been handling well before the incident.

"I had limited running today which was unfortunate," Barrichello said. "In this morning's session, a puncture cut my session short and then an off this afternoon also put me out early. The car felt quite loose before the incident and so we have a lot of things to look into now."

With the team only completing a total of 49 laps across both sessions, chief operations engineer Mark Gillan said that it has had to change its plans for the morning, but that it wasn't a completely fruitless day.

"We've had a difficult start to the weekend with not as much running as we had hoped for. Accordingly, we have now revised the running plan going into P3. We did improve the set-up between sessions one and two with some aero development and mechanical adjustments on the cars."